/*
 * Copyright (c) 2022-2023 Termony Co., Ltd. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this list of
 *    conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice, this list
 *    of conditions and the following disclaimer in the documentation and/or other materials
 *    provided with the distribution.
 *
 * 3. Neither the name of the copyright holder nor the names of its contributors may be used
 *    to endorse or promote products derived from this software without specific prior written
 *    permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "los_timer.h"
#include "los_config.h"
#include "los_tick.h"
#include "los_debug.h"
#include "los_arch_cpu.h"
#include "los_interrupt.h"
#include "los_arch_interrupt.h"

#define GENERIC_TIMER_NS_IRQ_NUM 30

STATIC UINT32 SysTickStart(HWI_PROC_FUNC handler);
STATIC UINT64 SysTickReload(UINT64 nextResponseTime);
STATIC UINT64 SysTickCycleGet(UINT32 *period);
STATIC VOID SysTickLock(VOID);
STATIC VOID SysTickUnlock(VOID);

STATIC ArchTickTimer g_archTickTimer = {
    .freq = 0,
    .irqNum = GENERIC_TIMER_NS_IRQ_NUM,
    .periodMax = LOSCFG_BASE_CORE_TICK_RESPONSE_MAX,
    .init = SysTickStart,
    .getCycle = SysTickCycleGet,
    .reload = SysTickReload,
    .lock = SysTickLock,
    .unlock = SysTickUnlock,
    .tickHandler = NULL,
};

STATIC UINT32 SysTickStart(HWI_PROC_FUNC handler)
{
    ArchTickTimer *tick = &g_archTickTimer;
    UINT64 timerVal = (UINT64) -1;
    UINT64 timerCtrl;
    UINT64 timerFreq;

    /* 通用定时器停止. */
    GET_ARM_SYS_REG(CNTP_CTL_EL0, timerCtrl);
    timerCtrl &= ~(1 << 0);
    SET_ARM_SYS_REG(CNTP_CTL_EL0, timerCtrl);
    __DSB();
    __ISB();

    /* 注册通道定时器中断回调函数. */
    HwiIrqParam irqParam = {tick->irqNum, NULL, "General Timer"};
    LOS_HwiCreate(tick->irqNum, OS_HWI_PRIO_HIGHEST, 0, handler, &irqParam);

    /* 获取通用定时器时钟频率. */
    GET_ARM_SYS_REG(CNTFRQ_EL0, timerFreq);
    tick->freq = (UINT32) timerFreq;
    /* 设置通用定时器绝对计数器值. */
    SET_ARM_SYS_REG(CNTP_CVAL_EL0, timerVal);

    /* 通用定时器中断使能. */
    timerCtrl &= ~(1 << 1);
    SET_ARM_SYS_REG(CNTP_CTL_EL0, timerCtrl);
    __DSB();
    __ISB();

    /* 通用定时器启动. */
    timerCtrl |= (1 << 0);
    SET_ARM_SYS_REG(CNTP_CTL_EL0, timerCtrl);
    __DSB();
    __ISB();

    return LOS_OK;
}

STATIC UINT64 SysTickReload(UINT64 nextResponseTime)
{
    UINT64 timerVal = (UINT64) -1;
    UINT64 current;

    GET_ARM_SYS_REG(CNTPCT_EL0, current);
    if ((current + nextResponseTime) > ((UINT64)-1)) {
        /* 设置通用定时器绝对计数器值. */
        SET_ARM_SYS_REG(CNTP_CVAL_EL0, timerVal);
        return ((UINT64)-1) - current;
    } else {
        /* 设置通用定时器相对计数器值. */
        SET_ARM_SYS_REG(CNTP_TVAL_EL0, nextResponseTime);
        return nextResponseTime;
    }
}

STATIC UINT64 SysTickCycleGet(UINT32 *period)
{
    UINT64 current;
    (VOID) period;

    GET_ARM_SYS_REG(CNTPCT_EL0, current);

    return current;
}

STATIC VOID SysTickLock(VOID)
{
    UINT64 timerCtrl;

    GET_ARM_SYS_REG(CNTP_CTL_EL0, timerCtrl);
    timerCtrl |= (1 << 1);
    SET_ARM_SYS_REG(CNTP_CTL_EL0, timerCtrl);
    __DSB();
    __ISB();
}

STATIC VOID SysTickUnlock(VOID)
{
    UINT64 timerCtrl;

    GET_ARM_SYS_REG(CNTP_CTL_EL0, timerCtrl);
    timerCtrl &= ~(1 << 1);
    SET_ARM_SYS_REG(CNTP_CTL_EL0, timerCtrl);
    __DSB();
    __ISB();
}

ArchTickTimer *ArchSysTickTimerGet(VOID)
{
    return &g_archTickTimer;
}

UINT32 ArchEnterSleep(VOID)
{
    __DSB();
    __WFI();
    __ISB();
    return LOS_OK;
}
